One of the most important rules of pest management is to identify the target before developing a control plan. Urban entomologists spend a significant amount of time identifying arthropods submitted for identification by technicians working in the field who are stumped, or simply looking for verification by an expert.

The duff millipede (Polyxenus spp.) can be a stumper if you don’t encounter it often. Photo: National Pest Management Association

Recently, a sample arrived at NPMA headquarters that our team initially placed confidently in “category b.” But we soon realized that the critters we were peering at were actually a solid “category c” mystery.

At first glance, the specimen looked like a tiny dermestid beetle larva — a pest that is submitted to our team multiple times each week. But something was off.

Closer inspection revealed two pairs of legs attached to each of its numerous body segments. The hairy little pest on the business end of our microscope turned out to be a duff millipede (family Polyxenidae). Duff millipedes are an occasional invader that can enter homes in large numbers, typically in search of moisture. Control is best achieved by sealing entry points and clearing away organic debris around the perimeter of the structure, where populations thrive. If it hadn’t been for our policy of getting peer confirmation on pest IDs, we might have suggested a completely different control tactic.

So, remember the immortal words of Han Solo as he reprimanded young Luke Skywalker a long time ago in a galaxy far, far away: “Don’t get cocky, kid.” Double-check your pest IDs, and get a second opinion if something seems amiss.